Combined float and mercury switch



June 17, 1952 c. J. KOCH, JR

COMBINED FLGAT AND MERCURY SWITCH Filed Nov. .10, 1949 1N VEN TOR. LAMP/ Es gf. /l/ocnr, r/.,

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ATTOR N EYS.

Patented June 17, 1952 UNITED STATES PATENT OFFICE COMBINED FLOAT AND MERCURY SWITCH Charles J. Koch, Jr., Cincinnati, Ohio Application November 10, 1949, Serial No. 126,635

(Cl. 20o-84) 3 Claims. l

My invention relates to an improved liquid level indicator comprising the combination oa float and a mercury switch.

Itis the primary object of my invention to provide improved means for informing one that a predetermined level of liquid has been obtained in a vat which is being fil-led with said liquid.

Another object of my invention is to provide an improved combination float and mercury switch which is extremely simple to manufacture and assemble.

A further object of my invention is to provide an improved signaling device such that only a slight deviation of the device from its normal position will result in the warning signal being given.

Still another object of my invention is to provide a iioat which will not only give a warning signal when slightly deviated from .its normal .position but also one that will maintain such signal even though the float be moved through an arc of almost 360 degrees.

A further object of my invention is to provide float of improved and simple construction as well as a novel and simple mercury switch which is easily mounted within said float.

Other objects and advantages of my invention will become apparent to one skilled in the art during the course of the following description and with reference to the attached drawings in which like numerals are employed to designate like parts throughout the same and in which Figure l is a partial section througha beer vat or the like showing the float in perspective as mounted within the vat and diagrammatically disclosing the signaling means,

Figure 2 is a section through .the float taken on the line 2--2 of Figure 1,

Figure 3 is an enlarged sectional view taken on the line 3 3 of Figure 2 and .showing the mercury switch in detail and its mounting within the float, and

Figure 4 is a sectional view tak-en on the line 4 4 of Figure 3.

Referring now to Figure 1, I have indicated a iioat i8 suspended by its cable II and a spring clip I2 from the wall I3-of a beer vat or the like. The level of the beer I4, or other liquid within the vat I3; is indicated at I4. The cable II encloses the two leads I5 and-I6 and is of conventional construction. This cable is shown as being provided with a conventional plug I1. Also shown in Figure 1, in diagrammatic form, .is a portable kit I8 containing a bell I-9 and light 20 and having aA socket 2'I adapted to receive the plug Il, said kit being provided with a plug 22 by means of which it may be connected to a conventional volt circuit or the like, not shown. I. have shown in Figure 1, in dot-dash lines, the position the oat IIlwill assume when the level of the liquid has risen from the level I4 to the level 23.

Referring now to Figure 2, it will-be noted that the oat which was generally indicated at IIJ in Figure 1 comprises two cylindrical portions 24 and 25. The upper portion 24v is shown as being provided with a thicker portion 26 which acts as weight for this end of the float. Although I have indicated the cylindrical portions 24' and 25, as .well as the thicker portion 2B, as being made of a plastic material it is to be understood that this does not constitute a limitation of my invention. It is to be further understood that rather than form the cylindricalportion 24 with the thicker portion 25, any conventional meansof providing additional weight to the upper end of that porY tion may be used. The upper portion 24 is adapted to receive theV cable II in such a way 'as-to form a very tight -t therewith. If necessary, a suitable adhesive or some other binder may br usedin order to secure such fit.

In order to simply and conveniently mount the mercury switch or the like within the iloat I0 I have provided the following construction, this being best seen in Figures'Z and 3. The upper portion 24 of the float Ill is provided with an internal shoulder 2'! and lange 28 While the lower cylindrical portion 25is formed with an external shoulder 29 and a flange 30. It will be noted that the flange 28 is Aof greater length than the flange 30 so that when a switch mounting disc 3| is positioned on the ange 30 and the shoulder Z-l brought into contact therewith, the flange 25 will be almost flush with the shoulder`29. A suitahlevadhesive, indicated at 32 in Figure may be provided in order to insure a tight connection between the cylindrical portions 24 and and the switch mounting disc 3|.

Referring now to Figures 3 and 4 the mercury switch which I have developed for use in connection with my improved liquid level indicator comprises a'sl'eeve 33 which is internally threaded so as toreceive the metal contactrplugs 34-and 35. The member -isprovided with al threaded extension i6-and the member 35.with athreaded extension 3l'. In order that `the metal contact plug member 3dmay be easily screwed into the sleeve 3.3, I have shown it as having a nut portion 38 formed integral therewith. Themember 35.is formed with asimilar nut-like;extension 39.

The member 35 is formed with a cup portion 40 and it is into this cupped portion 40 that the globule of mercury 4I is placed. A spacer ring 42 serves to keep the members 34 and 35 the correct distance apart from each other. It is to be understood that the sleeve 33 and spacer ring 42 are formed of some dielectric material. The cupped portion 45 ci the member 35 should be so constructed that it just nicely blends with the ring 42 so that there is substantially no ledge upon which bits of the mercury may come to rest. The cup 4-3 and spacer ring 42 are so arranged that when the switch is tilted just a slight bit from its normal vertical position. the globule of mercury 4I will ride to outer edges of the cupped portion 'I and thus make contact between the plug members 34 and 35. As best seen in Figures 2 and 3, the disc 3l is provided with an opening 43 through which the lead I5 is passed in order to be connected to the extension 3l, the extension 3'! being self passed through a hole 44 provided in this disc. If the leads I5 and :"6 are suitably connected to a source of electric current. such tilting of the member 35 and movement of the mercury 4I will complete the circuit through the extensions 3l', 3.5 and the members 34, 35. The nut 45 and washer 4E serve to properly attach the lead I5 to the extension 35 and the nut 4l washers 48 serve to properly attach the lead I5 to the extension 31'.

By way of construction then the member 35 may be screwed into the sleeve 33, the spacer ring 42 then dropped into contact with the member 35 and the mercury 4I placed in the cup portion 40 of this member 35. be screwed into the sleeve 33 against the spacer ring 42. Following this the member 35 is positioned on the disc 3i, the threaded extension 31 passing through the hole 34 of this disc. The disc 3| is then placed on the ilange 39 of the cylindrical member 25 and the lead passed through the opening 43 and into contact with the extension 31 against which it is maintained by means of the nut 41 and washers 48. Similarly the lead I6 is attached to the extension 35. The cylindrical portion 24 is then positioned S0 that its shoulder 2l rests on the disc 3I and the flange 23 brought adjacent the shoulder 29 of the cylindrical portion 25. A suitable adhesive 32 insures a liquid-tight connection of the portions 24 and 25. In this manner the mercury switch is maintained on the disc 3l and the disc 3I maintained in the lioat I 0.

It should be noted that the construction of the member 35 and its cup 4G and its relation to the member 34 through the spacer ring 42 is such that just a very slight tilting of the disc 3| results in the mercury 4! effecting an electrical contact between the members 34 and 35. It should be further noted that this contact will be maintained through substantially 360 degrees of movement of the switch for the globule of mercury 4I will ride between the members 34 and 35, against the spacer ring 42, until the switch again assumes the upright position indicated in Figure 3. Thus, not only is an electrical connection obtained by a very slight tilting of the oat I3 but also such contact is maintained through a very large swinging movement of this iloat.

In operation, a float constructed in the manner just described is suspended by means of its cable II and conventional spring clip I2 from the wall I3 of a beer vat or the like. I refer to a beer vat because it is in the beer industry that my invention will be particularly useful. I under- 'Ihe member 34 will then stand that it is now the common practice in the lling of beer vats to simply check them from time to time, by means of a stick or other such object, in order to determine whether or not the tank is substantially full. Many of the vats or tanks having been in existence for a great many years, it is quite often not possible to supply the tank with presently known liquid level indicators Without the expenditure of a great deal of time and money. The results of all this is that very often these vats are allowed to overow with a resulting waste of expensive material. As above indicated, my float will simply be positioned with respect to the vat wall I3 at any desired distance into the vat. It is contemplated that one of these iloats I9, cable I I and plug I7 will be provided for each vat. A kit containing a socket 2I, bell I9 and light 2U in series one with the other can then be plugged into a source of electrical current by the member 22. Two or three of such kits I8 will probably suiiice to service a brewery. The portable kit I8 is simply taken to the vat which is being filled, plugged into an electrical source and then the plug I'I inserted into the socket 2 I. When the level of the beer rises Within the vat to such .an extent that the float I0 is tilted slightly, contact is made in the manner above described and the circuit is completed through the members 34, 35, leads I5, I5 and the bell I9 and light 23 to the electrical source, the bell I9 and light 28 thus serving to warn the operator that the vat has been lled to the desired level.

In order to insure that my iloat will be sensitive in operation, I have provided the upper end thereof with the weighted portion 26 and also, I have arranged the portions 24 and 25 in such manner that the disc 3|, on which the switch is mounted, is located towards this upper weighted end of the oat IU. By such arrangement my float ID will be caused to tilt by liquid striking the portion 25 much more easily than if the upper portion 24 were not weighted and the switch located more nearly towards the center of the oat I0.

When a vat is to be lled with beer, the operator will see that the float I0 is suspended at the correct distance, bring his portable kit I8 to that tank and plug it into a suitable source of electricity, and then insert the plug II into the socket 2I In this manner I have provided a very simple and convenient means for the proper servicing of a large number of vats within a brewery so that the waste now incurred d-ue to an operators lack of knowledge of the liquid content of a particular vat is eliminated. Not only does a slight movement of the oat then result in the alarm being given, but also such alarm is not broken when the oat is given a still greater movement. Thus, when the iioat assumes its extreme position, as happens when the liquid level is as shown in Figure 1 at 23, the contact between the plates 34 and 35 by the mercury 4I will still be maintained.

It is to be understood that modiiications may be made in my invention without departing from the spirit or intent thereof, 'and it is to be further understood that I do not intend to be limited by the structure of the specific embodiment herein shown and described except insofar as that structure is set forth in the subjoined claims. Having thus described my invention what I claim as new and desire to protect by United States Letters Patent is:

1. In a liquid level indicator the combination of a oat and a mercury switch, said oat comprising two substantially cylindrical portions having interengaging flanges and shoulders, said switch being mounted Within said float on a disc engaged by said flanges and shoulders, and a lead carrying cable fixed in an end of one of said cylindrical portions so as to suspend said float and switch therefrom, said cable being connected through its leads to terminals provided for said switch and. te a source of electricity.

2. In a liquid level indicator the combination of a iioat and a mercury switch, said oat cornprising two substantially cylindrical portions having interengaging anges and shoulders, said cylindrical portions being of substantially different lengths, the shorter of said portions being weighted at its end opposite from the said interengaging flanges and shoulders, a disc mounted within said float by means of said interengaging iianges and shoulders, said switch being mounted on the side of said disc nearest said weighted end, and a lead carrying cable fixed in said weighted end so as to suspend said oat and switch therefrom, said cable being Iconnected through its leads to terminals provided for said switch and to a source oi electricity.

3. The device oi claim 2 in which said float is suspended from said cable in a vertical position when not in contact with a body of liquid, said switch being then in open position, whereby a slight tilting of said float caused by its contact with a said body of liquid will actuate said switch to closed position.

CHARLES J. KOCH, JR.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED' STATES PATENTS 

